Compensating XPM Using a Low-Bandwidth Phase Modulator

We experimentally demonstrate, for the first time, cross-phase modulation (XPM) compensation using an optical phase modulator and low-bandwidth electronics. We first show that our nonlinearity compensator suppresses the XPM distortion from a 10-Gb/s ON-OFF keyed (OOK) channel on a continuous-wave (CW) probe signal. We then replace the CW tone with a 28-Gbaud quadrature phase-shift keyed (QPSK) signal and show that the OOK power can be doubled when XPM compensation is used. This demonstrates proof-of-concept for XPM compensation using phase modulators placed along a fiber link.